Antenna feed adjusting means



Jan. 19, 1960 L. R. MATHESON ANTENNA FEED ADJUSTING MEANS Fil ed March 14, 1958 2 Sheets-Sheet 1 INVENTOR. LE 8415 H.1IA7'H5'60N Jan. 19, 1960 L. R. MATHESON 2, 0

ANTENNA FEED ADJUSTING MEANS Filed March 14, 1958 2 Sheets-Sheet 2 United States Patent ANTENNA FEED ADJUSTING MEANS Leslie R. Matheson, Binghamton, N.Y., assignor to the United States of America as represented by the Secretary of the Air Force Application March 14, 1958, Serial No. 721,613

4 Claims. '(Cl. 333-98) This invention relates, generally, to a means for adjusting the azimuth and elevation of an antenna feed or wave guide independently of the remaining components of the system. More particularly, the invention is concerned with providing a means for adjusting the waveguide of an airborne radar antenna whereby both the azimuth and elevation of the feed are adjusted by a single mechanism, thus eliminating the necessity of readjusting other parts of the system after changing a feed.

Devices presently in use for adjusting the feed to and from an airborne radar antenna have been useful to adjust in azimuth only and when it becomes necessary to change a feed, re-dowelling of the other components of the antenna is required. Therefore, the replacement of a feed usually consists of a long and tedious process of adjusting and readjusting the components of the antenna system. The present invention, however, overcomes this disadvantage by providing a means for adjusting the replaced feed in both azimuth and elevation at one particular junction point in the line thereby eliminating the necessity of realigning and re-dowelling the remaining portions of the antenna feed.

Accordingly, one of the primary objects of the present invention is to provide a novel device which is useful to adjust the feed system of an airborne radar antenna in both azimuth and elevation without realigning the remainder of the system.

Another object of the invention is to provide an adjusting means which is capable of suflicient accuracy to provide positive location and prevent relative motion among the feed components.

Still another object of the invention is to provide a device which is relatively simple in construction and requiring less manufacturing and assembly time. The use of fewer parts of unique design allows the device to be easily attached on the feed line yet being capable of accomplishing the desired result of adjusting in both azimuth and elevation.

These and other objects, features and advantages will become more apparent after considering the following detailed description taken in connection with the annexed drawings wherein:

Fig. 1 is a cross-sectional view of the adjusting clamp placed around a typical antenna feed system;

Fig. 2 is a top view of the device showing the position of wave guide feed in relation to the adjusting clamp;

Fig. 3 is a side view of the horseshoe plate member which encircles the wave guide including the cam surfaces which the wedge shaped segments contact;

Fig. 4 is an isometric view of the adjusting device with one of the wedge segments removed;

Fig. 5 is a view of the removed wedge shaped segment which fits between the cam surface of the plate and the wave guide showing the cam surface and threaded hole; and

Fig. 6 is an assembly view showing a wave guide in combination with the adjusting means embodying the principles of the present invention.

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Similar characters of reference are used in all of the above figures to indicate corresponding parts.

Referring now to Fig. 1 of the drawings, the horseshoe shaped plate 13 fits loosely around the wave guide 15. Clearance space 17 is allowed so that the plate 13 can be easily slipped around the wave guide 15. The plate 13 acts to fix the location of the shaft 19 with respect to the antenna (not shown) and holds the wave guide in proper relation therewith.

Two wedge shaped segments 21 and 23, having cam surfaces 25 and 27 machined thereon, fit between the wave guide and the respective cam surfaces 25' and 27 of the plate 13. The adjusting screws 29 and 31 cause the segments 21 and 23 to be drawn toward wave guide flange 33 along the cam surface 25, thereby forcing the Wedge segments 21 and 23 inward against the wave guide 15 and the plate 13 outward against the inner surface of the shaft 19. A key 35 is included to orient the wave guide 15 in the proper plane and to prevent rotation of the wave guide during operation of the radar antenna. Extra clearance is allowed in the openings in the plate 13 through which the adjusting screws 29 and 31 pass so that the plate 13 can move laterally without binding on the screws. A shoulder 37 is machined on the plate 13 in order to allow the shaft 19 to fit into position and be held when the open side of the plate 13 is expanded.

The plate member 13 is slipped around the wave guide 15 in the manner shown in Fig. 2. As shown, the adjustment of the feed in the direction of azimuth is accomplished by moving the feed and the wedge segments 21 and 23 with respect to the plate member 13.

In order to adjust the feed in elevation, one of the screws 29 or 31 is tightened while the other is loosened. The segments 21 and 23 slide upward or downward on the cam surfaces 25 and 27 of the plate 13 thereby setting the feed in the proper elevation direction. After the feed 15 is properly oriented both adjusting screws are tightened, forcing both segments against the cam surfaces of the plate and preventing further relative movement between the members by wedging the feed in the adjusted position and expanding the horseshoe plate 13 outward against the shaft 19 thus locking the entire feed system in its properly aligned position.

It will be apparent to those skilled in the art that the disclosed invention may be useful for other purposes besides those shown and described and it should be understood that various changes and modifications can be made to the embodiment described Without departing from the spirit and scope of the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Means for adjusting the feed system of a radar antenna including, a radar feed, a horseshoe shaped plate member dimensioned to loosely encircle three sides of said radar feed, said plate member having sloped cam surfaces thereon, a pair of wedge shaped segments having cam surfaces thereon adapted to engage the corresponding cam surfaces on said plate member, and independently operable bolt means connected to said feed and said wedge shaped segments to adjust the feed by urging one of said segments along one of said sloped cam surfaces inwardly against the side of the feed while the other of said segments moves along another of said sloped cam surfaces outwardly and radially away from the feed thereby moving one section of the feed relative to other sections thereof.

2. The adjusting means described in claim 1 wherein further relative movement among the components after adjustment is prevented by simultaneously tightening said independently operable bolt means in equal amounts, thereby locking the entire feed system.

3. Means for the adjustment of a radar antenna feed in both azimuth and elevation directions comprising, a radar feed, a horseshoe shaped plate member dimensioned to loosely encircle three sides of said radar feed, said plate member being provided with sufiicient clearance to allow considerable relative motion between itself and said feed for adjustment in the azimuth direction, means for adjusting said feed in the elevation direction including a pair of wedge shaped segments having cam surfaces thereon adapted to engage with corresponding cam surfaces on said plate member, and a pair of threaded bolts adapted to pass through a flange on said feed and through clearance openings in said plate member and into internally threaded openings in each of said wedge segments, tightening one of said bolts serving to urge one of said segments inwardly against the side of said feed while loosening the other of said bolts allowing said feed to move the other segment radially outward thereby permitting adjustmentv of the feed in the elevation direction.

4. Means for adjusting the feed system of a radar an- 2,92 2,1so I V 4 tenna including, a radar feed, a horseshoe shaped plate member dimensioned to loosely encircle three sides of a said radar feed, said plate being provided with a shoulder portion on its outer periphery, a tubular shaft having an inside diameter slightly greater than the shoulder portion of said plate member and adapted to slide onto said shoulder portion, a pair of wedge shaped segments having cam surfaces thereon adapted to engage corresponding cam surfaces on said plate member, bolt means for forcing said wedge segments into thearea between said feed and said plate thereby urging the open portion of said horseshoe shaped plate to open outwardly and hold said tubular shaft in its proper position relative to the rest of the feed system.

References Cited in the file of this patent UNITED STATES PATENTS 1,654,463 Jaques Dec. 27, 1927 1,774,678 Strid Sept. 2, 1930 2,038,554 Edgar Feb. 1, 1936 2,735,697 Zanin Feb. 21, 1956 

